A study on the electrical and optical characteristics of IGZO films

The electrical and optical properties of InGaZnO (IGZO) thin films were studied in the research. It was found that all the films deposited at room temperature exhibit amorphous structures. A better film quality was obtained at a lower pressure with sputtering ambiance. The RF power toward the IZO target was constant at 125 W; the RF power toward the Ga₂O₃ target varied from 0 to 70 W. A best IGZO film with corresponding resistivity, carrier concentration, and mobility is 7.94 × 10^?4 Ω-cm, 1.68 × 10²⁰ cm^?3, and 47 cm²/V-s, respectively. Due to the doping of gallium in the IGZO film, it led to a lower resistivity than that of the IZO film. A blue shift effect of the film was also observed in the doping of gallium to the IGZO film. The H₂ plasma effects toward the IGZO were also observed.